The cytotoxic effect of Baeckea frustescens extracts in eliminating hypoxic breast cancer cells.

BACKGROUND: Adaptive metabolic response towards a low oxygen environment is essential to maintain rapid tumour proliferation and progression. The vascular network that surrounds the tumour develops an intermittent hypoxic condition and stimulates hypoxia-inducing factors. Baeckea frutescens is used in traditional medicine and known to possess antibacterial and cytoprotective properties. In this study, the cytotoxic effect of B. frutescens leaves and branches extracts against hypoxic human breast cancer (MCF-7) was investigated. METHOD: The extracts were prepared using Soxhlet apparatus for ethanol and hexane extracts while the water extracts were freeze-dried. In vitro cytotoxic activities of B. frutescens extracts of various concentrations (20 to 160 µg/mL) at 24, 48, and 72 hours time points were studied using MTT in chemically induced hypoxic condition and in 3-dimensional in vitro cell culture system. An initial characterisation of B. frutescens extracts was carried out using Fourier-transform Infrared- Attenuated Total Reflection (FTIR-ATR) to determine the presence of functional groups. RESULTS: All leaf extracts except for water showed IC50 values ranging from 23 -158 µg/mL. Hexane extract showed the lowest IC50 value (23 µg/mL), indicating its potent cytotoxic activity. Among the branch extracts, only the 70% ethanolic extract (B70) showed an IC50 value. The hexane leaf extract tested on 3- dimensional cultured cells showed an IC50 value of 17.2 µg/mL. The FTIR-ATR spectroscopy analysis identified various characteristic peak values with different functional groups such as alcohol, alkenes, alkynes, carbonyl, aromatic rings, ethers, ester, and carboxylic acids. Interestingly, the FTIR-ATR spectra report a complex and unique profile of the hexane extract, which warrants further investigation. CONCLUSION: Adaptation of tumour cells to hypoxia significantly contributes to the aggressiveness and chemoresistance of different tumours. The identification of B. frutescens and its possible role in eliminating breast cancer cells in hypoxic conditions defines a new role of natural product that can be utilised as an effective agent that regulates metabolic reprogramming in breast cancer.

Toxicological aspects of Campomanesia xanthocarpa Berg. associated with its phytochemical profile.

Campomanesia xanthocarpa leaves are used as tea to treat diarrhea, inflammation, and hypercholesterolemia. Some pharmacological studies noted its beneficial uses of C. xanthocarpa; however, few investigations examined the toxicological profile of this plant. The aim of this study was to determine the chemical composition, genotoxic, and mutagenic potential of an aqueous extract of C. xanthocarpa leaves (CxAE), and potential protective effects against oxidative damage. Phytochemical constituents were determined using HPLC, and antioxidant effect in vitro was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical assay. Genotoxic effects and chromosomic mutations were assessed using comet assay and micronucleus (MN) test in Wistar rats treated with CxAE at 250, 500 or 1000 mg/kg for 7 consecutive days. Lipid peroxidation and antioxidant enzyme activities were measured in several tissues. CxAE induced mutations in TA98, TA97a, and TA102 strains. However, in the presence of metabolic activation, data were negative for all strains tested. Lack of mutagenicity was also observed in the MN test. This extract did not induce DNA damage, except when the highest concentration was used. DNA oxidative damage induced by hydrogen peroxide (H2O2) decreased in blood after treatment with CxAE. Lipid peroxidation levels were reduced while superoxide dismutase (SOD) activity increased in kidneys. The inhibitory concentration of CxAE required to lower DPPH levels to 50% was 38.47 ± 2.06 µg/ml. In conclusion, frameshift and oxidative mutations were observed only in the absence of metabolic activation which may be attributed to the presence of flavonoids such as quercetin. It is of interest that CxAE also showed protective effects against DNA oxidative damage associated with presence of ellagic acid, a phenolic acid with antioxidant activities. CxAE did not induce in vivo mutagenicity, suggesting that this extract poses a low toxic hazard over the short term.

Phytochemical Screening and Acute Toxicity of Aqueous Extract of Leaves of Conocarpus erectus Linnaeus in Swiss Albino Mice.

Mangroves represent areas of high biological productivity and it is a region rich in bioactive substances used in medicine production. Conocarpus erectus (Combretaceae) known as button mangrove is one of the species found in mangroves and it is used in folk medicine in the treatment of anemia, catarrh, conjunctivitis, diabetes, diarrhea, fever, gonorrhea, headache, hemorrhage, orchitis, rash, bumps and syphilis. The present study aimed to investigate the acute toxicity of aqueous extract of leaves of C. erectus in Swiss albino mice. The plant material was collected in Vila Velha mangroves, located in Itamaracá (PE). The material was subjected to a phytochemical screening where extractive protocols to identify majority molecules present in leaves were used. The evaluation of acute toxicity of aqueous extract of C. erectus followed the model of Acute Toxicity Class based on OECD 423 Guideline, 2001. The majority molecules were identified: flavonoids, tannins and saponins. The LD50 was estimated at 2,000 mg/kg bw. Therefore, the aqueous extract showed low acute toxicity classified in category 5.

Intoxicação espontânea e experimental por frutos de Eugenia uvalha Cambess (Myrtaceae) em ovinos / Spontaneous and experimental poisoning by fruits of Eugenia uvalha Cambess (Myrtaceae) in sheep

Descrevem-se os dados epidemiológicos, sinais clínicos e lesões de uma enfermidade de ovinos caracterizada por apatia, sialorréia, ranger de dentes, andar em círculos, cegueira, incoordenação motora, opistótono e convulsões, geralmente seguidos de morte. A doença ocorreu nos meses de fevereiro e março de 2009 a 2013, nas regiões Oeste e Planalto do Estado de Santa Catarina e está associada à queda dos frutos da "uvaieira" (Eugenia uvalha Cambess). Nas propriedades onde ocorreram os surtos havia grande quantidade de frutos caídos ao chão e os ovinos os consumiam avidamente. Os que sobreviveram permaneceram com convulsões intermitentes. Não foram observadas alterações macroscópicas ou histológicas. No entanto, foram encontrados frutos inteiros ou fragmentados, misturados ao conteúdo dos pré-estômagos e intestinos. A doença foi reproduzida a partir do fornecimento de frutos maduros de uvaia à três ovinos, nas doses diárias de 45,45g/kg, 68,18g/kg e 82,35g/kg por até seis dias. A principal forma de diagnóstico de intoxicação por "uvaia" é a observação do quadro clínico e epidemiológico, associado à presença de frutos e sementes no trato gastrointestinal.

We describe the epidemiological, clinical signs and lesions of a disease of sheep characterized by apathy, sialorrhoea, teeth grinding, circling, blindness, incoordination, seizures and opisthotonos usually followed by death. The disease occurred in February and March 2009 of 2013, in the West highlands and mountanous regions of Santa Catarina State and was associated with the falling fruits of "uvaieira" (Eugenia uvalha Cambess). In farms where outbreaks occurred had loads of fruit fallen to the ground and the sheep ate them hungrily. Those who survived remained with intermittent seizures. No gross or histological changes were observed. However, the whole fruits or their fragments mixed in the content of the pre-stomachs and bowels were found. The disease was reproduced providing the uvaia ripe fruits to three sheep, in daily doses of 45,45 g/kg, 68,18 g/kg and 82,35 g/kg each, for until six days. The main way to diagnose the uvaia poisoning is the observation of the clinical and epidemiological data, associated with the presence of fruits and seeds in the gastrointestinal tract.

Evaluación de la toxicidad subaguda del Camu-camu (Myrciaria dubia) administrado por vía oral en ratas / n vitro evaluation of the subacute toxicity of oral administration of (Myrciaria dubia) Camu-camu in rats / I

Camu-camu, es un árbol frutal, oriundo de la amazonía sudamericana que crece en las orillas anegables de ríos amazónicos. Pertenece al género Myrciaria, especie dubia. Presenta gran importancia nutritiva. Su alto contenido en ácido ascórbico (2780 mg/100 g de pulpa) le confieren propiedades antioxidantes. Objetivo: Evaluar la toxicidad subaguda (30 días) del Camu-camu. Material y método: Utilizamos 33 ratas albinas, macho, Holtzman, distribuidas en 3 grupos equitativos: Grupo I (grupo control), se le administró agua destilada, Grupo II y Grupo III, se les administró por vía oral el extracto seco de Camu-camu a las dosis de 100 y 200mg/Kg, respectivamente. Al inicio del experimento (basal), a las 15 y a los 30 días, se determinó: hemoglobina, WBC, urea, albúmina, creatinina, proteínas GGT, TGP, TGO, en sangre, y peso corporal; además, se realizó el examen histológico de hígado, riñones, bazo y estómago al finalizar el estudio (30 días). Resultados: Los valores de hemoglobina, albúmina y proteínas, fueron mayores que las del grupo control (p<0.05); a su vez, los valores de GGT fueron menores que los del grupo control (p<0.05). No encontramos evidencias de toxicidad sub-aguda, en ninguno de los 2 grupos expuestos, en el examen histopatológico. Conclusión: El Camu-camu, a las dosis y formas de administración, del presente trabajo, carece de efectos tóxicos para las ratas.

Camu-camu, is a native fruit tree of the South American jungle and grows at the borders of amazonian rivers. It belongs to Myrciaria generous and dubia specie and has a great nutritional importance. Contains a high amounts of ascorbic acid, (2780mg/100g of pulp), that is why it is good antioxidant. Objective: To evaluate the subacute toxicity of the atomized Camu-camu. Material and method: We used 33 Holtzman albino male rats, distributed in 3 equitable groups: Group I, the control group, only received distilled water, Groups II and III received 100 and 200 mg/Kg of Camu-camu, respectively. Blood samples were taken for biochemical analysis at the beginning, 15th and 30th days (at the end), to determinate Hb, WBC, urea, albumin, total proteins, creatinine, GGT, TGP, TGO and the weight of the animals; we also do the histological examination of liver, kidneys, spleen and stomach at the end of the experiments (day 30th). Results: The values of albumin, total proteins and hemoglobin were higher than the control group (p<0.05) while the values of GGT were lower that control group (p<0.05). We didnÆt find evidences of subacute toxicity in any of the 2 groups exposed to Camu-camu in the histopathological examination. Conclusion: Camu camu hadn´t toxic effect, in rats, with oral administration during 30 days.

Biochemical and toxicological studies of aqueous extract of Syzigium aromaticum (L.) Merr. & Perry (Myrtaceae) in rodents.

The effects of long-term administration of boiled aqueous extract of Syzigium aromaticum (SYZ), commonly known as clove (which has been locally employed for treating gastrointestinal tract diseases and also used as food spices), on some biochemical indices, such as body weight, liver functions and blood parameters were studied in adult albino rats of both sexes. Selected doses of 300 and 700 mg kg(-1) were given orally through cannular to groups of animals for a period of 90 days, while the control group received distilled water throughout the duration of study via the same route. Blood samples collected after therapy and assayed for activities of some liver enzymes recorded a significant (p<0.05) and prominent effect on ALP and AST. Measurement of haematological parameters also revealed significant effects (p<0.05; p<0.001) on Hb, RBC (p<0.05), PCV (p<0.001), platelets (p<0.001) and granulocytes (p<0.001). An insignificant reduction was recorded for total WBC. The histopathological study conducted was in consonance with the results of the biochemical investigations that the aqueous extract of SYZ even at moderate doses, significantly affects body organs, their enzymes as well as the various functions. LD(50) for both intraperitoneal and oral routes of SYZ were 263 and 2500 mg kg(-1) respectively. The present work has revealed the toxicity of sub chronic administration of SYZ, which suggests that its prolonged usage must be avoided.